Transcript for Instant Index: Trendy US Girls Names Over the Past 40 Years

Our "instant index" tonight adds a new video to our x files. Ufo? Decide for yourself. Here it comes, a glowingor shooting over the mountain top on a collision with a town in ice land. It's stirring up debate, a lot of people setting the tape, slowing it down. Some of them guess it's, in fact, a meteor or a drone. Somewhere the truth is out there. Like so many kids this high school student in the u.K. Was failing math. He buckled down for his long suffering dad and when he got a c on his report card he set up a camera to show it to his dad. Watch. My god? Are you sure? Yeah. One viewer wrote the boy, you're going to be all right if you have parents that love you so much. What's in a name. You can see the evolution of girls named by state for years. Mary reigning spraem. Lisa creeps in and by 1974 it's the united states of jennifer. Watch the names take hold in one REGION SPREAD IN THE 80s AND 90s. Jessica out west, ashley in the south. In recent times, of course, all those liz abellas and emmas everywhere. By the way, the source for this is a social security form.

This transcript has been automatically generated and may not be 100% accurate.

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